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Novel trisubstituted ethylenes, methyl and methoxy ring-trisubstituted 2-methoxyethyl phenylcyanoacrylates, RPhCH=C(CN)CO2CH2CH2OCH3 (where R is 2,3-dimethyl-4-methoxy, 2,5-dimethyl-4-methoxy, 2,4-dimethoxy-6-methyl, 3,5-dimethoxy-4-hydroxy, 4-hydoxy-3,5-dimethyl, 2,3,4-trimethoxy, 2,4,5-trimethoxy, 2,4,6-trimethoxy, 3,4,5-trimethoxy) were prepared and copolymerized with styrene. The ethylenes were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and 2-methoxyethyl cyanoacetate, and characterized by CHN analysis, IR, 1H and 13C NMR. All the ethylenes were copolymerized with styrene in solution with radical initiation (ABCN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis.

We employ synchrotron-based near-field infrared spectroscopy to reveal the vibrational properties of bulk, few-sheet, and single-sheet members of the MPS3 (M=Mn, Fe, Ni) family of materials and compare our findings with complementary lattice dynamics calculations. MnPS3 and the Fe analog are similar in terms of their symmetry crossovers, from C2/m to P3¯1m, as the monolayer is approached. These states differ as to the presence of a C3 rotation around the metal center. On the other hand, NiPS3 does not show a symmetry crossover, and the lack of a Bu symmetry mode near 450 cm-1 suggests that C3 rotational symmetry is already present, even in the bulk material. We discuss these findings in terms of local symmetry and temperature effects as well as the curious relationship between these symmetry transformations and those that take place under pressure.

We employ synchrotron-based near-field infrared spectroscopy to reveal the vibrational properties of bulk, few-sheet, and single-sheet members of the MPS3 (M=Mn, Fe, Ni) family of materials and compare our findings with complementary lattice dynamics calculations. MnPS3 and the Fe analog are similar in terms of their symmetry crossovers, from C2/m to P3¯1m, as the monolayer is approached. These states differ as to the presence of a C3 rotation around the metal center. On the other hand, NiPS3 does not show a symmetry crossover, and the lack of a Bu symmetry mode near 450 cm-1 suggests that C3 rotational symmetry is already present, even in the bulk material. We discuss these findings in terms of local symmetry and temperature effects as well as the curious relationship between these symmetry transformations and those that take place under pressure.

We measured the near-field infrared response of MnPS3 in bulk, few-, and single-layer form and compared our findings with traditional far-field vibrational spectroscopies, a symmetry analysis, and first-principles lattice dynamics calculations. Trends in the Bu mode near 450cm-1 are striking, with the disappearance of this structure in the thinnest sheets. Combined with the amplified response of the activated Ag mode and analysis of the Au+Bu features, we find that symmetry is unexpectedly increased in few- and single-sheet MnPS3 due to a restoration of the threefold axes of rotation. Monoclinicity in this system is therefore a consequence of the long-range stacking pattern and temperature rather than local structure.

Surgical resection is the treatment of choice for most intracranial meningiomas. We review the current state of adjuvant therapies, including radiation and chemotherapy. Conventional external beam radiation and stereotactic radiosurgery remain second-line options for patients unwilling or unable to undergo surgery. Radiation therapy is most useful in the setting of recurrent or residual tumor after surgical resection, where it is associated with a clear increase in the length of progression-free survival. This survival advantage is most pronounced with high-grade meningiomas, which have a much higher recurrence rate than low-grade meningiomas, even after gross total resection. In contrast, the role of chemotherapy in the treatment of meningiomas is limited. This treatment modality is often reserved for inoperable tumors or those refractory to radiation treatment. Furthermore, the choice of chemotherapy agents is limited. Hydroxyurea, a ribonucleotide reductase inhibitor, has modest clinical activity in meningiomas. In recent small clinical trials, somatostatin analogues have been moderately effective in controlling tumor growth.

Central neurocytomas of the posterior third ventricle are rare. These typically benign lesions have recently been shown to respond well to Gamma knife stereotactic radiosurgery (SRS). We present the case of a posterior third ventricle central neurocytoma presenting with aqueduct obstruction. The patient was treated with endoscopic biopsy and endoscopic third ventriculostomy, followed by Gamma knife radiosurgery. At 2 years the tumor has diminished in size and the patient is neurologically intact. This treatment strategy may avoid the risk of open ventricular surgery and the need for shunts in patients with central neurocytomas of appropriate size and location.

Foxp3-expressing regulatory T (T reg) cells have been implicated in parasite-driven inhibition of host immunity during chronic infection. We addressed whether parasites can directly induce T reg cells. Foxp3 expression was stimulated in naive Foxp3⁻ T cells in mice infected with the intestinal helminth Heligmosomoides polygyrus. In vitro, parasite-secreted proteins (termed H. polygyrus excretory-secretory antigen [HES]) induced de novo Foxp3 expression in fluorescence-sorted Foxp3⁻ splenocytes from Foxp3-green fluorescent protein reporter mice. HES-induced T reg cells suppressed both in vitro effector cell proliferation and in vivo allergic airway inflammation. HES ligated the transforming growth factor (TGF) β receptor and promoted Smad2/3 phosphorylation. Foxp3 induction by HES was lost in dominant-negative TGF-βRII cells and was abolished by the TGF-β signaling inhibitor SB431542. This inhibitor also reduced worm burdens in H. polygyrus-infected mice. HES induced IL-17 in the presence of IL-6 but did not promote Th1 or Th2 development under any conditions. Importantly, antibody to mammalian TGF-β did not recognize HES, whereas antisera that inhibited HES did not affect TGF-β. Foxp3 was also induced by secreted products of Teladorsagia circumcincta, a related nematode which is widespread in ruminant animals. We have therefore identified a novel pathway through which helminth parasites may stimulate T reg cells, which is likely to be a key part of the parasite's immunological relationship with the host.

The basic problem in Jamaica is in modernizing the outlook and sense of values of a traditional agricultural population. Only 75% to 80% of the population is literate thereby making communications difficult. The National Family Planning Board was set up in 1967 and today there are 121 centers on the island. In addition there is a voluntary Jamaica Family Planning Association. The curriculem at the University of the West Indies has been undergoing change. In the Department of Obstetrics and Gynecology the students are taught clinical aspects of family planning in detail. In the Department of Social and Preventive Medicine the accent is more on the community and its sociological demographic and economic aspects. A recent innovation is joint seminars with other departments.

Accounting for over one-twelfth of world trade and by far the largest movement of people across borders, international travel has been promoted by governments and the tourism industry as an important facilitator of global citizenship. It has been commonplace in the tourism literature to argue that tourism can and does function as an important contributor to the development of the attributes of global citizenship such as international and cross-cultural understanding, tolerance and sharing of values, mutual support, disabusing of stereotypes and exchange of values (Ketabi, 1996). Notwithstanding this global mobility, evidence of global citizenry and the tolerance it promotes is far from ubiquitous.